Ventilation type vacuum photovoltaic window system and system optimization method based on ventilation mode

Abstract

The invention discloses a ventilation type vacuum photovoltaic window system and a system optimization method based on a ventilation mode, and relates to the technical field of vacuum photovoltaic window design and optimization. The technical problem that high power generation efficiency of a photovoltaic module in the daytime and low heat loss at night are difficult to take into account in an existing ventilation vacuum photovoltaic window installed in a cold high-altitude area at present is solved. The photovoltaic glass module and the vacuum glass module are included, an air cavity is formed between the photovoltaic glass module and the vacuum glass module, light-transmitting opening and closing plates are arranged on the upper side and the lower side of the photovoltaic glass module and the upper side and the lower side of the vacuum glass module respectively, and the light-transmitting opening and closing plates are opened and closed to form ventilation openings which are opened and closed independently. Corresponding sides, far away from the air cavity, of the photovoltaic glass module and the vacuum glass module are communicated with the air cavity through the ventilation openings respectively; the invention aims to give consideration to both high power generation efficiency of a photovoltaic module in daytime and low heat loss at night.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photovoltaic windows, and particularly relates to a ventilation type vacuum photovoltaic window system and a system optimization method based on a ventilation mode. BACKGROUND

[0002] Photovoltaic glass is composed of two glass plates and a series of strip or block solar cells encapsulated between the glass plates. Compared with traditional glass, photovoltaic glass can weaken the penetration of indoor solar radiation due to the cell coverage, and can also reduce glare. In order to achieve building energy saving, combining photovoltaic glass with windows is an effective way to optimize the performance of windows, which has the characteristics of combining the function of solar radiation energy conversion with the function of building materials. Photovoltaic windows realize the functional upgrading of building envelope systems by integrating photoelectric conversion units into window structures, thereby forming photovoltaic power generation for building power supply and achieving active reduction of building energy consumption. The ventilation vacuum photovoltaic window is a combination of photovoltaic glass components and vacuum glass components into a window body, forming a controllable air flow channel between the two, and setting openable air inlet and outlet ports on the upper and lower ends or side ends of the channel, so that the air cavity can be switched between closed, indoor circulation connected with the room, and outdoor circulation connected with the room, thereby realizing the adjustment of comprehensive performance such as heat preservation and heat dissipation through ventilation heat exchange while generating electricity.

[0003] The plateau is affected by high altitude, complex topographic features and special atmospheric circulation, forming the plateau continental climate characteristics. According to the results of building thermal division in China, it belongs to the severe cold and cold climate zone. The winter is long and cold, and the summer is cool. The winter of the plateau is significantly longer than the summer, and a large amount of energy needs to be consumed to meet the building heating demand. The conventional energy of the plateau is generally poor, but the solar energy resources are abundant, so the photovoltaic window technology can be reasonably applied in this area to utilize the abundant solar energy resources in this area to alleviate the problem of large energy consumption. However, the existing photovoltaic windows mainly emphasize power generation and shading, but in cold regions, especially in high-altitude areas, the temperature difference between day and night is large, and the solar radiation is very strong during the day. The photovoltaic components and heat absorption layer will heat up. If the heat is not dissipated, the photovoltaic window is easy to heat, the temperature of the photovoltaic component is increased, and the photovoltaic power generation efficiency is low. However, if the photovoltaic window is designed to dissipate heat in time during the day, the indoor heat will be dissipated by the photovoltaic window at night, which will increase the heating burden. Therefore, the ventilation vacuum photovoltaic window installed in the cold high-altitude area often has the problem of being difficult to balance the high power generation efficiency of the photovoltaic component during the day and the low heat dissipation during the night. SUMMARY

[0004] To solve the above technical problems, the present application provides a ventilation type vacuum photovoltaic window system, which is characterized in that: a photovoltaic glass module and a vacuum glass module are combined, an air cavity is formed between the two modules, and a light-transmitting opening and closing plate is arranged on the upper and lower sides of the photovoltaic glass module and the vacuum glass module to form an independently openable and closable ventilation opening, the ventilation opening penetrates the corresponding side of the photovoltaic glass module and the vacuum glass module away from the air cavity.

[0005] The technical scheme adopted by the present application is as follows:

[0006] The ventilation type vacuum photovoltaic window system comprises a photovoltaic glass module and a vacuum glass module, an air cavity is formed between the photovoltaic glass module and the vacuum glass module, and a light-transmitting opening and closing plate is arranged on the upper and lower sides of the photovoltaic glass module and the vacuum glass module, the light-transmitting opening and closing plate is opened and closed to form an independently openable and closable ventilation opening, and the ventilation opening penetrates the corresponding side of the photovoltaic glass module and the vacuum glass module away from the air cavity.

[0007] Preferably, the photovoltaic glass module comprises two glass plates, a photovoltaic cell array is encapsulated between the two glass plates, and the area ratio between the photovoltaic cell array and the glass plates, i.e., the cell coverage rate CCR, is 0.1-0.9.

[0008] Preferably, the vacuum glass module comprises two parallel glass plates and a plurality of support columns, an air gap is arranged between the two glass plates, and the plurality of support columns are arranged at intervals in the air gap.

[0009] Preferably, the width-to-height ratio D / H of the air cavity is 0.03-0.15.

[0010] Preferably, a LOW-E coating is arranged on the glass plate of the vacuum glass module, the LOW-E coating is arranged on the side close to the air gap, and the infrared surface emissivity of the glass plate provided with the LOW-E coating is 0.02-0.22.

[0011] Preferably, the distance between two adjacent support columns is 28-32 mm, and the diameter of the support column is 0.3 mm.

[0012] Preferably, the thickness of the air gap is 0.2 mm, and the vacuum pressure is 0.001 Pa.

[0013] The system optimization method based on the ventilation mode is used to optimize the ventilation type vacuum photovoltaic window system as described above, and the steps of the system optimization are as follows:

[0014] Step 1: Establish a comprehensive energy consumption influence formula;

[0015] Step 2: Based on the energy consumption formula, study the influence of four parameters, i.e., cell coverage rate CCR, width-height ratio D / H, infrared surface emissivity, and opening degree of the ventilation opening, on the comprehensive energy consumption under different ventilation modes;

[0016] Step 3: Based on the influence of the four parameters on the comprehensive energy consumption under different ventilation modes, perform a single variable experiment to find the optimized value of each parameter;

[0017] Step 4: Based on the lowest comprehensive energy consumption, perform optimization of the combination of the four parameters under different ventilation modes.

[0018] Preferably, when the ventilation type vacuum photovoltaic window system is installed on an external window of a building, the area ratio of the window to the entire wall where the current window is installed WWR is greater than or equal to 85%.

[0019] As described above, due to the adoption of the above technical solutions, the beneficial effects of the present application are as follows:

[0020] 1. By combining the photovoltaic glass module and the vacuum glass module, and forming an air cavity between them, and by setting the light-transmitting opening and closing plates which can be independently opened and closed at the upper and lower ends to form ventilation openings, the air cavity has a controllable air flow organization structure while maintaining the lighting conditions; the photovoltaic glass module limits the cell coverage rate CCR to 0.1-0.9, so that the window has the ability to generate electricity while moderately weakening the solar radiation entering the indoor; the vacuum gap and support column structure of the vacuum glass module further reduce conduction and convection heat transfer, providing a stable heat insulation basis for night heat preservation in cold high-altitude areas;

[0021] 2. By setting the air cavity and restricting the radiation heat transfer path, a structure that can dissipate heat during the day and insulate heat at night is realized; the width-height ratio D / H of the air cavity is limited to 0.03-0.15, so that the cavity has both the channel conditions to form effective ventilation and heat exchange, and the heat recovery efficiency is maximized; at the same time, a LOW-E coating is set on the side close to the vacuum gap, and the infrared surface emissivity is controlled to 0.02-0.22, thereby suppressing the radiation heat transfer related to the vacuum layer, reducing the overall heat transfer coefficient, reducing the tendency of heat loss from the window to the outside during low temperature periods, and improving the night heat preservation performance;

[0022] 3. Set up a seasonal optimization method based on ventilation mode, limit the window-wall ratio WWR≥85% when installing the outer window, which is beneficial to expand the effective layout area of photovoltaic and improve the contribution of photovoltaic power supply, so that it can more effectively reduce the comprehensive energy consumption of buildings in the scene of sufficient solar energy resources but lack of conventional energy on the plateau in the form of power generation and thermal regulation coordination. BRIEF DESCRIPTION OF DRAWINGS

[0023] The present application will be described by way of example and with reference to the accompanying drawings, in which:

[0024] Figure 1 is a schematic diagram of experimental measurement point arrangement in the present application;

[0025] Figure 2 is a schematic diagram of the connection structure of a ventilation type vacuum photovoltaic window system in the present application;

[0026] Figure 3 is a schematic diagram of the influence of different cell coverage rates on the annual energy consumption structure in the present application;

[0027] Figure 4 is a schematic diagram of the comprehensive influence of different cell coverage rates on the annual energy consumption in the present application;

[0028] Figure 5 is a schematic diagram of the influence of different air cavity width-height ratios D / H on the annual energy consumption structure in the present application;

[0029] Figure 6 is a schematic diagram of the comprehensive influence of different air cavity width-height ratios D / H on the annual energy consumption in the present application;

[0030] Figure 7 is a schematic diagram of the influence of different infrared surface emissivities on the annual energy consumption structure in the present application;

[0031] Figure 8 is a schematic diagram of the comprehensive influence of different infrared surface emissivities on the annual energy consumption in the present application;

[0032] Figure 9 is a schematic diagram of the influence of different ventilation opening degrees on the annual energy consumption structure in the present application;

[0033] Figure 10 is a schematic diagram of the comprehensive influence of different ventilation opening degrees on the annual energy consumption in the present application;

[0034] Figure 11 is an energy consumption diagram of each ventilation mode after optimization of structural parameters in the present application.

[0035] REFERENCE NUMERALS

[0036] 1 - light-transmitting opening and closing plate, 2 - vacuum gap, 3 - support column, 4 - coating, 5 - air cavity, 6 - photovoltaic cell array. DETAILED DESCRIPTION

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0038] The following is combined Figures 1-11 The present invention will be described in detail below.

[0039] An experimental platform was constructed in an open area in Xinduqiao Town, Kangding City, Ganzi Tibetan Autonomous Prefecture, Sichuan Province (101°53′E, 30°02′N, altitude 3457.1m). The experimental space was oriented 17° west of south, with no buildings or vegetation obstructing the south facade to ensure unobstructed solar radiation reception for the south-facing windows. The enclosure structure was constructed using double-layer rock wool sandwich color steel composite panels to form a low thermal conductivity enclosure system, minimizing the interference of wall thermal conductivity on experimental data. A ventilated vacuum photovoltaic window system was installed on the south-facing wall of the room.

[0040] The data collection methods are as follows, please refer to the appendix. Figure 1 Experimental measurement point setup:

[0041] 1. Environmental data acquisition: Mobile thermal index meter HD32.3TC, i.e., microclimate data acquisition instrument ( Figure 1 (As shown in the gray block) is placed outside the experimental room to record the ambient air temperature, humidity and wind speed in the area near the wall of the experimental room; the TBQ-2 total solar radiation sensor is installed on the south facade, connected to the data acquisition and controller, and automatically records the solar irradiance of the vertical facade.

[0042] 2. Power generation data acquisition: The MP-11 IV curve tracker, manufactured by EKO Instruments, measures and records the current, voltage, and power generation of the photovoltaic glass module;

[0043] 3. Thermal performance data acquisition: Sensors, including 17 thermocouples, 1 conduction heat flux meter, and 1 radiation heat flux meter, were installed on the experimental platform. These probes were connected to the CR1000X data acquisition and controller via the thermocouple expansion board AM25T.

[0044] The DF-25 T type thermocouple is used to measure the temperature of various surfaces of glass, the temperature of air inside the cavity, and the air temperature of the outdoor near-wall area and the indoor center. The thermocouples are calibrated in a constant temperature bath before measurement.

[0045] HS-30 heat flux meterFigure 1 (As shown in the green square) is installed at the center of the inner surface of the window to measure the heat flow conducted through the innermost surface of the vacuum photovoltaic window;

[0046] TBQ-2 Solar Total Radiation Sensor Figure 1 (As shown in the orange square) It is installed on the inside of the window to record the solar irradiance transmitted through the window;

[0047] RS-30 Radiant Heat Flux Meter Figure 1 (As shown in the yellow square) is installed approximately 30mm apart from the center of the inner side of the test window to measure the total radiative heat flow through the vacuum photovoltaic window;

[0048] Testo440 hot-wire anemometer Figure 1 The red square (as shown in the middle) is placed in the openings at the top and bottom of the ventilated vacuum photovoltaic window to measure the wind speed and temperature at the inlet and outlet.

[0049] In the above experimental measurements, the temperature and heat flow data collected by the heat flow meter and thermocouples, as well as the solar radiation intensity collected by the total solar radiation sensor, were uploaded to the accompanying software and recorded by the CR1000X data acquisition and controller. The temperature data is displayed as a direct temperature value, while the heat flow data is displayed as a voltage signal, which is converted using the specific parameter values ​​corresponding to each sensor. The ventilation volume, electrical performance parameters, and experimental parameters of outdoor environmental conditions recorded by the hot-wire anemometer were all recorded and uploaded by their respective accompanying software.

[0050] The embodiments and comparative examples in this application are based on measurements under four ventilation modes (internal circulation, external circulation, closed, and ventilation). The specific implementation methods of the four modes are as follows:

[0051] Enclosed: All light-transmitting opening and closing plates 1 of the vacuum photovoltaic window system are closed, that is, all ventilation openings are closed, the air cavity 5 is not connected to the outside, and the heat inside the air cavity 5 cannot be discharged;

[0052] Ventilation: When all the light-transmitting opening and closing plates 1 of the vacuum photovoltaic window system are opened, that is, all the ventilation openings are opened, the air cavity 5 is connected to the indoor and outdoor air, so that the indoor air is connected to the outdoor air, forming convection heat exchange in the air cavity 5.

[0053] Internal circulation: Only the light-transmitting opening and closing plate 1 on the vacuum glass module side is opened, and indoor air enters the air cavity 5 from the lower vent, and then is discharged back into the room from the upper vent through thermal pressure;

[0054] External circulation: Only the light-transmitting switch 1 on the photovoltaic glass module side is opened, and outdoor air enters the air cavity 5 from the lower vent, and then is discharged back to the outside through the upper vent via thermal pressure, thereby removing the heat from the air cavity 5.

[0055] The position corresponding relationship of the LOW-E coating 4 on the glass plate of the vacuum glass module in the present application is: 1-located on the side close to the air cavity 5; 2-located on the outer side close to the vacuum gap 2; 3-located on the inner side close to the vacuum gap 2; 4-located on the side close to the indoor.

[0056] To ensure that the ventilation cross-sectional area and the geometric characteristics of the air cavity 5 maintain a proportional relationship, the ventilation opening degree α is defined as the ratio of the actual opening height to the reference height; the specific parameter corresponding relationship is: when the opening degree α=1, the ventilation opening is fully open, and when α=0, the ventilation opening is closed; the ventilation opening degree decreases by 0.1, and the opening height decreases by 10%.

[0057] Embodiment 1

[0058] A ventilation type vacuum photovoltaic window system, with reference to the accompanying drawings Figure 2 , comprising a photovoltaic glass module and a vacuum glass module, an air cavity 5 is formed between the photovoltaic glass module and the vacuum glass module, and the upper and lower sides of the photovoltaic glass module and the vacuum glass module are respectively provided with light-transmitting opening and closing plates 1, which are independently opened and closed by opening and closing to form ventilation openings that penetrate the air cavity 5 on the corresponding side of the photovoltaic glass module and the vacuum glass module away from the air cavity 5.

[0059] Among them, the photovoltaic glass module and the vacuum glass module are respectively fixed with the side wall of the installation wall; the thickness of the air cavity 5 is 120mm;

[0060] Among them, the photovoltaic glass module side, i.e. the upper and lower light-transmitting opening and closing plates 1 close to the outdoor, adopts tempered glass with a thickness of 5mm, and the vacuum glass module side, i.e. the upper and lower light-transmitting opening and closing plates close to the indoor, adopts vacuum glass with a thickness of 10.2mm.

[0061] In the present embodiment, the photovoltaic glass module comprises two glass plates, a photovoltaic cell array 6 is encapsulated between the two glass plates, and the area ratio between the photovoltaic cell array 6 and the glass plate, i.e. the cell coverage rate CCR, is 0.7.

[0062] Among them, the photovoltaic cell array 6 adopts a cadmium telluride thin film photovoltaic component with a thickness of 0.6mm, which has a flexible, lightweight structure and high integration adaptability; the thickness of the two glass plates is 3.2mm, the glass plate close to the outdoor adopts super-white float glass, and the glass plate close to the air cavity 5 side adopts semi-tempered glass.

[0063] In the present embodiment, the vacuum glass module comprises two parallel glass plates and a plurality of support columns 3, a vacuum gap 2 is arranged between the two glass plates, and a plurality of support columns 3 are arranged at intervals between the vacuum gap 2.

[0064] The thickness of the glass plate is 5mm, and the thermal conductivity of the glass is 1W / (m.K).

[0065] In this embodiment, the width-height ratio D / H of the air cavity 5 is 0.06.

[0066] In this embodiment, the glass plate of the vacuum glass module is provided with a LOW-E coating 4, which is arranged on the side close to the vacuum gap 2. The infrared surface emissivity of the glass plate provided with the LOW-E coating 4 is set to 3-0.12.

[0067] In this embodiment, the opening degree of the ventilation port is set to 0.5.

[0068] In this embodiment, the distance between two adjacent support columns 3 is 30mm, the diameter of the support column 3 is 0.3mm, the height of the support column 3 is 0.2mm, and the support column 3 is a steel column.

[0069] In this embodiment, the thickness of the vacuum gap 2 is 0.2mm, and the vacuum pressure is 0.001Pa.

[0070] In this embodiment, the window occupies 85% of the area of the wall on which the current window is installed.

[0071] Example group 2

[0072] Different from example 1, the battery coverage of this example group is set to 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.8 and 0.9 respectively.

[0073] Example group 3

[0074] Different from example 1, the width-height ratio D / H of the air cavity of this example group is set to 0.03, 0.04, 0.05, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14 and 0.15 respectively.

[0075] Example group 4

[0076] Different from example 1, the infrared surface emissivity and position of this example group are set to 1-0.02, 2-0.02, 3-0.02, 4-0.02, 1-0.12, 2-0.12, 4-0.12, 1-0.22, 2-0.22, 3-0.22, 4-0.22, and the infrared surface emissivity of the LOW-E coating 4 is set to 0.84.

[0077] Example group 5

[0078] Different from example 1, the opening degree of the ventilation opening α in this example group is respectively 0.1, 0.2, 0.3, 0.4, 0.6, 0.7, 0.8, 0.9 and 1.

[0079] The total energy consumption in the closed mode, the inner circulation mode (night closed), the outer circulation mode (night closed) and the ventilation mode is measured respectively under the conditions of example 1 to example group 5 as follows, wherein the night closed time is from 6 pm to 10 am the next day;

[0080] The total energy consumption is composed of the lighting energy consumption, the heating energy consumption, the refrigeration energy consumption and the power generation, and the structural design parameters of the ventilation type vacuum photovoltaic window affect the thermal, light and electrical performance of the structure, and the thermal, light and electrical performance of the window structure affects the heating, refrigeration, lighting energy consumption and power generation of the building.

[0081] The comprehensive energy consumption formula is used: , wherein Q0 represents the annual comprehensive energy consumption of the building, kWh; Q heating represents the heating energy consumption, kWh; Q cooling represents the refrigeration energy consumption, kWh; Q lightig represents the annual lighting energy consumption, kWh; Q pv represents the annual power generation, kWh; the energy consumption simulation results of the vacuum photovoltaic window are analyzed, and in order to reflect the influence of photovoltaic power generation on the overall energy consumption, the annual energy consumption consumption is subtracted by the annual photovoltaic power generation as the building comprehensive energy consumption;

[0082] The influence of the cell coverage rate (CCR) on the annual energy consumption structure is shown in the attached Figure 3As shown, when CCR≤0.3, the total energy consumption is dominated by refrigeration energy consumption, and in closed mode, the refrigeration energy consumption of 233.47 kWh is 14.4 times that of heating 16.25 kWh, accounting for 75.8% of the total energy consumption; after CCR≥0.4, the heating energy consumption exceeds the refrigeration energy consumption, such as in closed mode CCR=0.5, the heating energy consumption of 113.4 kWh accounts for 63.8%, and the refrigeration energy consumption is reduced to 36.1%; in the external circulation mode, when CCR=0.9, the refrigeration energy consumption is only 0.01 kWh, but the heating energy consumption reaches 804.63kWH, accounting for 99.2% of the total energy consumption; the proportion of lighting energy consumption continues to decline as CCR increases, from 19.0% in closed mode CCR=0.1 to 12.1% in CCR=0.9; the ventilation mode shows a significant overall advantage in plateau areas, when CCR=0.5, the total energy consumption of 180.69 kWh is reduced by 34.7% compared with the closed mode, and the power generation is 554.39 kWh, which can cover 3 times the energy consumption, and the energy self-sufficiency rate reaches 307%; when CCR=0.7, the absolute value difference between power generation and total energy consumption is the largest, that is, more power can be generated to supply the building for use; its dynamic regulation and control capability balances the demand of extreme climate, when CCR=0.8, the refrigeration energy consumption is only 0.86 kWh, which is 0.62 kWh higher than that in the external circulation mode, but the heating energy consumption is 233.94 kWh lower, which has the characteristics of low load and high capacity, and is suitable for the whole year energy efficiency optimization demand in the plateau strong radiation and large temperature difference environment.

[0083] As shown in FIG. 4, the overall energy consumption of the closed mode, the external circulation mode and the ventilation strategy of the ventilation mode presents a trend of first decreasing and then increasing with the battery coverage rate, and when the battery coverage rate is 0.7 and the ventilation strategy is adopted, the overall energy consumption of the whole is the lowest, reaching-578.68kWh. The overall energy consumption of the internal circulation mode decreases with the increase of the battery coverage rate, indicating that the waste heat generated by high battery coverage rate is more conducive to heat recovery in the internal circulation mode. When the battery coverage rate is 0.2, the overall energy consumption of the external circulation mode reaches 0.93kWh, and the building energy consumption can reach-1.20kWh after adopting the ventilation strategy, and the overall energy consumption decreases to negative. When the battery coverage rate is greater than 0.3, the overall energy consumption of several ventilation modes can be less than zero. When the coverage rate is 0.1, the overall energy consumption of the external circulation mode is the lowest, and the ventilation strategy is between closed and external circulation due to dynamic switching mode. With the increase of the coverage rate to 0.2-0.7, the energy saving advantage of the ventilation strategy is significantly improved, and the overall energy consumption is reduced by 53.8%-10.3% compared with the closed mode. When the coverage rate is 0.8-0.9, the overall energy consumption of the internal circulation mode is better than that of the ventilation strategy, and the internal circulation mode can reduce the energy consumption under high coverage rate. Therefore, the ventilation strategy has significant advantages under medium and high coverage rate (0.3-0.7), and the internal circulation mode is more targeted under high coverage rate.

[0084] The impact of the cavity aspect ratio (D / H) of a ventilated vacuum photovoltaic window on annual energy consumption is as follows: Figure 5 As shown, when the D / H ratio increases from 0.03 to 0.15, the total energy consumption of all modes shows a decreasing trend. In ventilation mode, the total energy consumption drops from 201.76 kWh to 186.23 kWh, a decrease of 7.7%. The proportion of lighting energy consumption remains stable at 30%-32%, such as 31.9% (59.5 / 186.48 kWh) when D / H=0.1. Heating dominates the energy consumption structure, with the proportion of heating consistently exceeding 58% under the ventilation strategy. For example, when D / H=0.03, heating energy consumption is 124.22 kWh, accounting for 61.6% of the total energy consumption, and it decreases slightly as D / H increases, specifically to 115.92 kWh when D / H=0.15. The proportion of cooling energy consumption gradually increases with increasing D / H, rising from 9.0% at D / H=0.03 to 0.03. The energy consumption ratio was 6.2%; energy consumption relationship critical point analysis showed that cooling energy consumption exceeded heating energy consumption only in the internal circulation mode in the D / H=0.03-0.04 range. For example, when D / H=0.03, cooling energy consumption of 148.83 kWh was significantly higher than heating energy consumption of 108.88 kWh, accounting for 46.7%. This is related to heat accumulation caused by nighttime closure. Under ventilation strategy control, its energy consumption and power generation synergy was the best. For example, when D / H=0.06, the power generation of 774.73 kWh could cover the total energy consumption of 196.05 kWh, which was 3.95 times, and the net capacity reached 578.68 kWh, which was better than the closed mode. Compared with the external circulation mode, when D / H=0.03, heating energy consumption was 326.6 kWh, the ventilation strategy demand was reduced by 61.9%, while cooling energy consumption was controlled at 18.08 kWh, which was only 12.1% of the internal circulation mode, showing outstanding adaptability to extreme climates. In addition, its power generation increased with D / H The increased attenuation rate is slightly lower than that of the internal circulation mode; therefore, in high-altitude areas, the ventilation mode with D / H=0.06-0.09 is preferred, with a total energy consumption of about 186-196kWh. While ensuring heating efficiency in winter, the cooling energy consumption is controlled at 17.76-15.56kWh, which is suitable for the year-round energy efficiency optimization needs in high radiation and low humidity environments.

[0085] See attached document Figure 6, D / H pair on the comprehensive energy consumption, D / H (cavity width-height ratio) and ventilation mode significantly affect the comprehensive energy consumption (negative value represents energy saving effect). The comprehensive energy consumption of internal circulation mode, closed mode and ventilation strategy continues to optimize with the increase of D / H, the comprehensive energy consumption of closed mode decreases from-517.93 kWh to-538.03 kWh, which is optimized by 3.9%; the ventilation strategy decreases from-572.83 kWh to-587.90 kWh, which is optimized by 2.6%; the internal circulation mode decreases from-456.12 kWh to-482.61 kWh, which is optimized by 5.8%; the external circulation mode (night closed) has the highest comprehensive energy consumption (-386.34 kWh) when D / H=0.03, and reaches the lowest comprehensive energy consumption (-394.38 kWh) when D / H=0.04. The ventilation strategy has the lowest comprehensive energy consumption (-587.90 kWh) when D / H=0.15, which is the best choice.

[0086] The influence of the infrared surface emissivity of the ventilated vacuum photovoltaic window on the annual energy consumption is as follows Figure 7As shown, low emissivity coating (e.g. 4-0.02) can significantly reduce heating energy consumption, with heating demand decreasing from 108.78 kWh (0.84) to 82.99 kWh (2-0.22) under ventilation strategy, but accompanied by an increase in cooling energy consumption to 33.61 kWh, an increase of 12.2%. When the emissivity increases from 0.02 to 0.22 at the same location (e.g. location 1), the heating energy consumption decreases significantly: from 205.61 kWh (1-0.02) to 108.57 kWh (1-0.22) under ventilation strategy, a decrease of 47.2%, but the cooling energy consumption increases by 271% (8.58 to 29.79 kWh). In addition, low emissivity (0.02) leads to an increase in heating energy consumption, for example 1-0.02, the heating energy consumption accounts for 75.6% in the ventilation strategy; high emissivity (0.22) slightly increases the cooling load, especially the internal circulation mode 2-0.22 configuration cooling energy consumption accounts for 69.3%; without coating (0.84), the thermal imbalance of the external circulation mode is the most serious, and the heating energy consumption increases to 302.84%. Under the same emissivity, the energy consumption of different locations is significantly different. At 0.02 emissivity, the heating demand of location 3 is the lowest (147.81 kWh under ventilation strategy), which is 28.1% lower than that of location 1; at 0.12 emissivity, the total energy consumption of location 3 is optimal (180.51 kWh), and the cooling energy consumption accounts for 13.3% (23.99 kWh); at 0.22 emissivity, the heating energy consumption of location 2 is only 82.99 kWh, but the cooling energy consumption increases to 33.61 kWh, reflecting the regulatory effect of location layout on thermal balance. Location 4 has the highest power generation of -774.68 kWh at low emissivity (0.02), which is 0.1% higher than that of location 1.

[0087] Referring to the drawings Figure 8, the infrared surface emissivity on the comprehensive energy consumption. The energy-saving effect is weak under low emissivity (0.02), and the energy-saving effect is better when the emissivity is 0.12-0.84, such as the ventilation strategy at position 2 (emissivity 0.22) comprehensive energy consumption reaches the optimal energy saving-599.06 kWh. The ventilation strategy is always the most energy-saving, especially when the emissivity is ≥0.12, the comprehensive energy consumption (-562.05~ -599.06 kWh) is significantly better than other modes, and its dynamic switching mechanism (such as daytime external circulation cooling, night internal circulation heat preservation) balances the annual energy consumption demand. The comprehensive energy consumption of the closed mode at a high emissivity of 0.22 is-536.63 kWh, which is better than the internal circulation mode, indicating that complete sealing can reduce heat leakage. In terms of material selection, high-emissivity materials (such as no Low-E coating, emissivity ≥0.12) are preferred to enhance radiation heat dissipation and reduce cooling energy consumption. The ventilation strategy is the optimal solution, the external circulation mode is limited to the summer high-temperature scenario, and the closed and internal circulation modes are suitable for the winter dominant region.

[0088] The influence of the opening degree of the ventilation port of the ventilation type vacuum photovoltaic window on the annual energy consumption is shown in Figure 9 The opening degree of the ventilation port of the ventilation type vacuum photovoltaic window in the plateau region presents a nonlinear regulation characteristic. When the opening degree increases from 0.1 to 1, the cooling energy consumption of the internal circulation mode increases from 92.95 kWh to 165.44 kWh, with an increase of 78.0%, and when the opening degree is 0.6, the cooling energy consumption (152.09 kWh) is higher than the heating energy consumption (103.59 kWh), accounting for 59.5%, indicating that the use of internal circulation mode during the day will cause indoor overheating. The heating dominant ventilation strategy energy consumption structure, the heating energy consumption ratio is always higher than 60%, the cooling energy consumption ratio is stable at 8.7-10.4%, which is significantly better than the cooling energy consumption ratio (36.4-61.8%) of the internal circulation mode; the external circulation mode has very low cooling energy consumption, which is between 3.60-13.25 kWh, but the heating demand is as high as 238.66-349.06 kWh, and the heating / cooling ratio is between 18:1-97:1, and the energy consumption ratio is seriously unbalanced. Except for the internal circulation mode, the heating energy consumption is always dominant in other modes, and the heating / cooling ratio of the closed mode is stable at 2.69:1 (137.4 kWh vs. 51.01 kWh). Under the ventilation control strategy, increasing the opening degree of the ventilation port can simultaneously reduce the heating and cooling energy consumption, for example, when the opening degree is 0.1, the heating energy consumption is 124.06 kWh and the cooling energy consumption is 20.26 kWh, and when the opening degree is 1, the heating energy consumption is 119.33 kWh and the cooling energy consumption is 17.03 kWh, while the power generation efficiency is improved, the power generation capacity increases from 773.84 kWh to 774.99 kWh, realizing a total energy consumption reduction of 3.8% and a net energy production increase of 0.15%.

[0089] Refer to the drawings Figure 10 , the influence of the opening degree of the ventilation port on the comprehensive energy consumption, the comprehensive energy consumption in closed mode is constant at -524.57 kWh, and in internal circulation mode, it increases from -503.72 kWh when the opening degree is 10% to -445.85 kWh when the opening degree is 100% (the energy saving effect decreases by 11.5%). In external circulation mode, it increases from -464.08 kWh when the opening degree is 10% to -365.59 kWh when the opening degree is 100% (the energy saving effect decreases by 21.2%). After adopting the ventilation strategy, the comprehensive energy consumption increases from -570.03 kWh when the opening degree is 10% to -579.14 kWh when the opening degree is 100% (the energy saving effect increases by 1.6%). The ventilation strategy strengthens heat dissipation in summer (reduces cooling energy consumption) and maintains heat preservation in winter (reduces heating demand) through intelligent switching mode, while the single circulation mode is difficult to balance due to seasonal contradictions, resulting in deterioration of the comprehensive energy consumption throughout the year.

[0090] Example 6

[0091] The above-mentioned ventilation type vacuum photovoltaic window system is optimized in combination with the ventilation mode, and the steps of system optimization are as follows:

[0092] Step 1: establish the comprehensive energy consumption influence formula as described above;

[0093] Step 2: based on the energy consumption formula, study the influence of four parameters, namely cell coverage rate CCR, width-height ratio D / H, infrared surface emissivity, and opening degree of the ventilation port, on the comprehensive energy consumption in different ventilation modes;

[0094] Step 3: as in Examples 1-5, based on the influence of the four parameters on the comprehensive energy consumption in different ventilation modes, single variable experiments are conducted to find the optimized values of each parameter;

[0095] Step 4: based on the lowest comprehensive energy consumption, the optimization of the combination of the four parameters in different ventilation modes is performed, and a set of optimized structural parameters of the vacuum photovoltaic window in different ventilation modes is obtained; the optimized structural parameters of the vacuum photovoltaic window in different ventilation modes according to Table 1 below are set.

[0096] Table 1: optimized structural parameters of the vacuum photovoltaic window in different ventilation modes

[0097]

[0098] After adopting the final optimized structural parameter combination of Example 6, the energy consumption characteristics of several ventilation modes are as follows Figure 11The energy consumption of each mode is shown in the table. From the energy consumption performance of each mode, the ventilation strategy has the lowest comprehensive energy consumption and the best performance, with heating (85.30 kWh) and cooling (20.20 kWh) energy consumption significantly lower than other modes; the power generation of the closed mode reaches 773.31 kWh, and the comprehensive energy consumption reaches-552.42 kWh, only second to the ventilation strategy; the total energy consumption of the internal circulation mode (night closed) reaches 491.20 kWh, far exceeding other modes; the comprehensive energy consumption of the external circulation mode (night closed) reaches-506.40 kWh, and the internal and external circulation modes are not suitable for use throughout the year, but if combined with seasonal regulation, the energy consumption can be greatly reduced.

[0099] By comparing the comprehensive energy consumption data of the comparative experiment structure and the optimized structure, the energy-saving effect of each ventilation mode shows significant differences. Although the basic structure determined by the experiment is the relatively optimal structure selected according to theoretical research, through the analysis of climate adaptability and optimization of structure size for high-altitude and strong-radiation cold regions, the energy-saving performance can still be improved to a certain extent. The energy consumption and energy-saving effect of each ventilation mode are shown in Table 3. In the closed mode, the comprehensive energy consumption decreases from-524.57 kWh to-552.42 kWh, the energy consumption decreases by 27.85 kWh, the heating energy consumption decreases by 38.37 kWh, but the cooling energy consumption increases by 11.32 kWh. The optimized structure may reduce heat loss in winter by enhancing the thermal insulation performance, but the insufficient heat dissipation capacity in summer leads to an increase in cooling demand. In the internal circulation mode (night closed), the comprehensive energy consumption decreases from-462.95 kWh to-501.72 kWh, the energy consumption decreases by 38.77 kWh, and the optimized structure selects a battery coverage rate of 0.9, which increases the heat recovery efficiency and power generation efficiency, resulting in a significant increase in power generation of 219.49 kWh, a sharp decrease in cooling energy consumption of 144.36 kWh, and a sharp increase in heating energy consumption of 316.25 kWh. In the external circulation mode (night closed), the energy consumption decreases the most, with the comprehensive energy consumption decreasing from-392.95 kWh to-506.40 kWh, and the energy consumption decreasing by 113.45 kWh. The heating energy consumption decreases by 140.63 kWh, and the cooling energy consumption increases by 25.78 kWh. Due to the use of D / H of 0.04, the cavity flow rate slows down, the heat accumulates in the cavity, and the power generation efficiency decreases, resulting in a slight decrease in power generation of 1.56 kWh. The comprehensive energy consumption of the ventilation strategy decreases from-578.68 kWh to-610.57 kWh, the energy consumption decreases by 31.89 kWh, the heating energy consumption decreases by 33.50 kWh, the cooling energy consumption slightly increases by 2.44 kWh, the total energy consumption decreases by 31.02 kWh, and the power generation slightly increases by 0.87 kWh. Since the closed mode and the ventilation strategy use the same optimized structure, the energy consumption of the closed mode after optimization is-552.42 kWh, and the comprehensive energy consumption can still decrease by 58.15 kWh after using the ventilation strategy, which illustrates the importance of seasonal regulation of the ventilation type vacuum photovoltaic window for energy saving in high-altitude regions.

[0100] Table 2: Comparison of energy consumption and energy-saving effect of ventilation modes

[0101]

[0102] It should be noted that:

[0103] The foregoing description of the disclosed embodiments enables a person skilled in the art to make or use the application. Modifications of these embodiments will occur to persons of skill in the art, and, while certain modifications are discussed, it is desired to be protected in accordance with the spirit and scope of the application. Therefore, the application is not limited to the specific embodiments shown and described, but only by the scope of the appended claims, unless otherwise specified.

Claims

1. A ventilated vacuum photovoltaic window system, characterized in that, The system includes a photovoltaic glass module and a vacuum glass module. An air cavity (5) is formed between the photovoltaic glass module and the vacuum glass module. Light-transmitting opening and closing plates (1) are respectively provided on the upper and lower sides of the photovoltaic glass module and the vacuum glass module. The light-transmitting opening and closing plates (1) form independently openable and closed ventilation ports by opening and closing. The ventilation ports respectively connect the corresponding sides of the photovoltaic glass module and the vacuum glass module away from the air cavity (5) to the air cavity (5).

2. The ventilated vacuum photovoltaic window system according to claim 1, characterized in that, The photovoltaic glass module includes two glass plates, and a photovoltaic cell array (6) is encapsulated between the two glass plates. The area ratio between the photovoltaic cell array (6) and the glass plate, i.e., the cell coverage ratio (CCR), is 0.1~0.

9.

3. The ventilated vacuum photovoltaic window system according to claim 2, characterized in that, The vacuum glass module includes two parallel glass plates and multiple support columns (3). A vacuum gap (2) is provided between the two glass plates, and the multiple support columns (3) are arranged at intervals between the vacuum gap (2).

4. A ventilated vacuum photovoltaic window system according to claim 1, characterized in that, The aspect ratio D / H of the air cavity (5) is 0.03~0.

15.

5. A ventilated vacuum photovoltaic window system according to claim 3, characterized in that, The glass plate of the vacuum glass module is provided with a LOW-E coating (4), which is located on the side close to the vacuum gap (2). The infrared surface emissivity of the glass plate with the LOW-E coating (4) is set to 0.02~0.

22.

6. A ventilated vacuum photovoltaic window system according to claim 3, characterized in that, The distance between two adjacent support columns (3) is 28~32mm, and the diameter of the support column (3) is 0.3mm.

7. A ventilated vacuum photovoltaic window system according to claim 3, characterized in that, The thickness of the vacuum gap (2) is 0.2 mm and the vacuum pressure is 0.001 Pa.

8. A system optimization method based on ventilation patterns, characterized in that, The ventilation-type vacuum photovoltaic window system according to any one of claims 1 to 7 is optimized by combining ventilation modes. The system optimization steps are as follows: Step 1: Establish the formula for the comprehensive energy consumption impact; Step 2: Based on the energy consumption formula, study the impact of four parameters—battery coverage ratio (CCR), aspect ratio (D / H), infrared surface emissivity, and the degree of ventilation opening—on the overall energy consumption under different ventilation modes; Step 3: Conduct single-variable experiments to find the optimal value for each parameter based on the impact of the four parameters on the overall energy consumption under different ventilation modes; Step 4: Optimize the combination of four parameters under different ventilation modes based on the lowest overall energy consumption.

9. The system optimization method based on ventilation mode according to claim 8, characterized in that, When a ventilated vacuum photovoltaic window system is installed on a building's exterior window, the window occupies an area of ​​≥85% of the entire wall surface where the window is installed.

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